1. Field of the Invention
The present invention relates to voltage detection devices capable of detecting an input voltage of an inverter device.
2. Description of the Related Art
There are known voltage detection devices which detect an input voltage to be supplied to an inverter device. For example, a patent document 1, Japanese patent laid open publication No. JP S51-084279, discloses a voltage detection device which has a voltage detection section and an additional reference voltage generation circuit. The additional reference voltage generation circuit generates a plurality of reference voltages. The conventional voltage detection device corrects a detection error of an offset voltage and a gain error of the voltage detection section by using the generated reference voltages.
Specifically, the conventional voltage detection device disclosed in the patent document 1 (JP S51-084279) corrects a detection error generated in the voltage detection device on the basis of the reference voltage generated by the reference voltage generation circuit and a detection voltage detected when the voltage detection section inputs the reference voltage through input terminals of the voltage detection section.
It is necessary to increase the detection accuracy of the voltage detection device when the voltage detection device is used for an inverter device. The inverter device converts a direct current (DC) power to an alternating current (AC) power. The inverter device detects a voltage necessary for protecting and controlling the inverter device.
The voltage detection device increases its detection accuracy when equipped with the additional reference voltage generation circuit. However, this significantly increases a manufacturing cost of the voltage detection device because of having the additional reference voltage generation circuit and increasing the total number of components thereof.
However, it is possible to increase the detection accuracy of the voltage detection device without using the additional reference voltage generation circuit by adjusting the detection accuracy of the voltage detection device in order to have the optimum detection accuracy in an inspection step during its manufacturing process. However, this method cannot correct any error of the voltage detection section generated by time-dependent change.